There is an article on the best rechargeable batteries over on "MetaEfficient.com". To summarize, the Ni-MH batteries are the best. They break down the pros and cons of a few brands. To go a step further, they also rate a few of the "best" chargers for these batteries.

For me, the benefit is a relatively quick recharge time, 6 or 8 hours typically and most newer chargers go automatically to trickle mode when the battery is full. This means I can keep batteries in the charger and they are ready when I need them.

What I find typically is that you only need to recharge the batteries 3 times to break even on the cost of the battery itself. If you have a pack of 4 AA batteries and a 4 AA battery charger, the set will pay for itself after about 8 recharges. That is still pretty quick and it is very beneficial for the environment.

Use rechargeables wherever it is reasonable.

To see the article at MetaEfficient.Com, follow the related link below.